 (fact (identical? 2 2M)      => false) ; Not surprising
 (fact (identical? 2 2.0M)    => false) ; Not surprising
 (fact (identical? 2.0 2.0)   => false) ; Not surprising
+
+;;; But then I found this:
+(fact (identical?  127  127) => true)
+(fact (identical?  128  128) => false)
+(fact (identical? -128 -128) => true)
+(fact (identical? -129 -129) => false)
+;;; /Clojure Programming/ p433 says:
+;;;     The exception is that the JVM (and therefore Clojure) provides for a
+;;;     limited range of fixnums. Fixnums are a pool of boxed integer values
+;;;     that are always used in preference to allocating a new integer. [...]
+;;;     The Oracle JVM’s fixnum range is ±127.
 
 ;;;; ---------------------------------------------------------------------------
 ;;;; ---- `=` ----

;;;; ---- `identical?` ----
;;;; Tests whether two arguments are the same object.

(fact (identical? 2 2)       => true)  ; Of course
(fact (identical? 2N 2N)     => false) ; Possibly surprising
(fact (identical? 2/3 2/3)   => false) ; Possibly surprising

;; Maybe mention java.math.BigInteger

;;;; ___________________________________________________________________________
;;;; ---- =-and-same-type ----

(defn =-and-same-type
